Some of the advice that you are getting here is not good. Don't shout. That's not projection.
A well-supported voice comes from a release of air by not tensing the facial muscles, good posture, a relaxed stance leaning toward the ball of the toes (like a boxer), allowing the breath to come in without tension, stay in relaxed motion and don't hold anything.
You don't need much air, just enough to go through the vocal cords, but the volume comes through releasing the breath, not forcing it. Rigid tension is the enemy of voice production.
Don't over enunciate because this causes rigidity in the facial muscles which must be fluid and relaxed at all times. Don't stop the air by clipping the sound with consonants.
Hawaiian and Italian voices are strong because of the pure vowel sounds in their language unimpeded by consonants that cut the sound off.

The Alexander Technique will help to acquire the proper relaxation for performance.